Composite microfibers from polystyrene and cellulose nanowhiskers were produced by electrospinning. The morphology of the microfibers was examined by using scanning and transmission electron microscopies. Surface porosity, unique ribbon-shapes, and the presence of twists along the fiber axis were observed in the composite microfibers. Thermomechanical properties of processed nanocomposites were studied by differential scanning calorimetry and dynamical mechanical analyses. The reinforcing effect of cellulose nanowhiskers was confirmed as the glassy modulus of electrospun microfibers increased with nanowhisker load. This effect is explained to be the result of mechanical percolation of cellulose nanowhiskers forming a stiff and continuous network held by hydrogen bonding. It is demonstrated that cellulose nanoparticles can be used effectively to reinforce hydrophobic matrices and to produce unique structural properties, enabling new functionalities and properties.

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Cellulose nanoparticles obtained by acid hydrolysis of cellulose paper were used to reinforce polystyrene composite films. The nonionic surfactant sorbitan monostearate was utilized to improve the dispersion properties of the hydrophilic cellulose in hydrophobic matrix and to prevent the formation of aggregates. Turbidity tests were used to measure dispersion stability of the cellulose crystallites in the hydrophobic solvent used in the composite manufacture. A correlation was found between the dispersion stability in solvent and the formation of aggregates in the polymeric composites. Nanocomposite films were processed using a casting/evaporation technique. Thermal and mechanical properties of processed composites were studied by differential scanning calorimetry (DSC) and dynamical mechanical analyses (DMA), respectively. The results showed that the optimum addition of surfactant produced better dispersion of the cellulose particles in the polystyrene matrix and improved the mechanical properties of the resulting composite due to an enhanced compatibility. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

In light of environmental concerns, the textile industry has accelerated efforts to reduce or eliminate water consumption in all areas of yarn preparation, dyeing, and finishing. Supercritical fluid dyeing technology has the potential to accomplish this objective in many commercial textile applications around the world, both at present and in the future around the world. Increased interest in this technology has made a fundamental understanding of thermophysical (equilibrium solubility) and transport (kinetics) properties of such fluids and fluid mixtures necessary. Supercritical carbon dioxide (SC-CO2) is one of the most environmentally acceptable solvents in use today, and textile processes using it have many advantages when compared to conventional aqueous processes. − Positive environmental effects range from drastically reduced water consumption to eliminating hazardous industrial effluent. Furthermore, economic benefits include increased productivity and energy savings. Successfully commercializing supercritical fluid CO2 processing will improve the economics of dyeing and other textile chemical processes by eliminating water usage and wastewater discharges and increasing productivity by reducing processing times as well as required chemicals and auxiliaries and reducing energy consumption and air emissions. As a result, SC-CO2 processing will be more rapid, more economical, and more environmentally friendly.

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